Most producing oil wells within the Provinces of Alberta and Saskatchewan are set up in a similar fashion. A drive head is positioned on a well head. A production flow line extends from the well head to a liquid storage tank, which is spaced a distance from the well head. A propane burner shoots flame into a fire tube in the liquid storage tank. An engine positioned in a wooden shack adjacent to the well head, provides motive force to the drive head. Propane tanks positioned adjacent to the liquid storage tank, provide a fuel source for the propane burner and the engine respectively.
Referring to FIG. 5, there is illustrated a prior art well site, generally indicated by reference numeral 100. Well site 100 includes a liquid storage tank 12 having an interior 14, a peripheral sidewall 16 and a heat tube 17. A primary propane tank 20 provides fuel to a burner 21. A secondary propane tank 23 provides fuel to an engine 24 that is housed separate and apart from liquid storage tank 12. Hydraulic flow lines 26 driven by hydraulic pump 48 extend from engine 24 to drive head 28. A production line 30 extends from a well head 32 to liquid storage tank 12.
U.S. Pat. No. 7,726,298 (St. Denis) entitled “Method and apparatus for heating a liquid storage tank” describes an apparatus for heating a liquid storage tank. Referring to FIG. 1, the apparatus, generally indicated by reference numeral 10, includes a liquid storage tank 12 having an interior 14, a peripheral sidewall 16, and an engine compartment 18 appended to liquid storage tank 12. Referring to FIG. 2, primary propane tank 20 provides fuel through fuel line 22 to engine compartment 18. Referring to FIGS. 1 and 3, an engine 24 is disposed within engine compartment 18. Referring to FIG. 2, hydraulic flow lines 26 extend from engine compartment 18 to drive head 28. A production line 30 extends from well head 32 to liquid storage tank 12. Hydraulic flow lines 26 are in a substantially parallel orientation and in close proximity to production line 30. Referring to FIG. 3, engine 24 has exhaust manifold 34 which is connected to an exhaust conduit 36 which extends from peripheral sidewall 16 into interior 14 of storage tank 12. Exhaust conduit 36 is depicted as a substantially horizontal loop that, upon exiting peripheral sidewall 16, is adapted with a muffler 38. Exhaust conduit 36 is further adapted with interior baffles 40. An engine coolant conduit 42 extends from engine 24. A thermostatically controlled valve 44 is positioned along engine exhaust conduit 36. From thermostatically controlled valve 44, engine coolant conduit 42 extends below exhaust conduit 36. Referring to FIGS. 3 and 4, engine coolant conduit 42 is depicted as being positioned below the exhaust conduit 36 and proceeds horizontally below the exhaust conduit 36 and returns to engine 24. Referring to FIG. 3, in addition, engine coolant conduit 42 may extend to a booster pump 46 that also returns engine coolant to engine 24. Depending upon the orientation of thermostatically controlled valve 44, the flow of heated engine exhaust may proceed by either the coil or by pass route. Engine 24 is further adapted with hydraulic pump 48 that provides hydraulic pressure to hydraulic flow lines 26.
Referring to FIG. 3, engine 24 is operated within engine compartment 18. Referring to FIG. 2, fuel for the operation of engine 24 is provided by propane tank or casing gas. 20. No other source of fuel is needed. The noise of engine 24 is dampened by muffler 38 and absorption of sound by liquid storage tank 12 through peripheral sidewall 16. Heat 50, given off from engine 24 during operation, heats engine compartment 18 and such heat is transferred through peripheral sidewall 16 to interior 14 of liquid storage tank 12. Hot exhaust gases 52 from engine 24 pass through exhaust conduit 36 and heat 50 given off heats interior 14 of liquid storage tank 12. Interior baffles 40 disrupt the linear flow of hot exhaust gases 52 to more evenly distribute and transfer heat from hot exhaust gases 52 through exhaust conduit 36 to interior 14 of liquid storage tank 12. Referring to FIG. 4, in the illustrated embodiment, engine coolant conduit 42 is disposed below the exhaust conduit 36. Heated engine coolant passes through engine coolant conduit 42 such that heat 50 is added to further transmit heat 50 to interior 14 of liquid storage tank 12. Referring to FIG. 3, for operation in warmer conditions, thermostatically controlled valve 44 diverts heated engine exhaust, to the bypass route. Allowing 50% of the engine heat out of the 14 tank interior, the heated engine coolant is cooled and, in turn, moderates the temperature of interior 14 of liquid storage tank 12. Referring to FIGS. 1 and 2, apparatus 10, by configuring hydraulic lines 26 in a substantially parallel orientation and in close proximity to production line 30, production fluid within production line 30 is also heated.
Referring to FIGS. 6 through 8, in some circumstances, the fluids held in liquid storage tank 12 contain suspended solids, or solids are transported with the fluids as they are deposited in liquid storage tank 12, such as sand. As the liquids are stored, the solids settle out and come to rest on the bottom of tank 12. When this is the case, the fluids stored in storage tank 12 can be more effectively heated by raising engine compartment 18 relative to the bottom of liquid storage tank 12, such that at least a portion of the engine compartment is inset within the periphery of the storage tank 12 at a higher position than would otherwise be the case. As it is raised, it may be necessary to include a floor 54 with rails 56, a support 58, and stairs 60 shown in FIG. 7. Referring to FIG. 8, compartment 18 may also have a vent 62, and an engine guard 65 to prevent individuals from entering the compartment during operation.